[BUG] Claude doesn't update itself on Windows 11

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

I have a workstation on which Claude could never update itself, while it does on another one.
In the meantime I've tried cleaning up app registrations, uninstalling, installing via different ways (winget, claudesetup) without success.
When going to File -> Help -> Check for Updates, it will report that there is an update but says it will be downloaded in the background. After that nothing happens. The menu shows that there was an issue with the previous installation.

The main.log shown below.

What Should Happen?

Claude should download the latest version and update itself, prompting to restart.

Error Messages/Logs

2026-09-29 22:30:32 [info] [updater] Checking for updates
2026-09-29 22:30:33 [info] [updater] Found an update, downloading
2026-09-29 22:30:33 [error] [updater] Auto-update error: [Error: Deployment is NULL. See http://go.microsoft.com/fwlink/?LinkId=235160 for diagnosing.] {
  [stack]: [Getter/Setter],
  [message]: 'Deployment is NULL. See http://go.microsoft.com/fwlink/?LinkId=235160 for diagnosing.'
}

Steps to Reproduce

File -> Help -> Check for Updates

Claude Model

Sonnet (default)

Is this a regression?

No, this never worked

Last Working Version

_No response_

Claude Code Version

2.1.220 (Claude Code)

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Windows Terminal

Additional Information

The update only works if I run ClaudeSetup.exe again.

claude update in terminal will update something but the GUI will still show a pending update and fail to install it.